The present invention pertains generally to sprayer assemblies. More specifically, the present invention pertains to disposable sprayer assemblies which can be connected to a garden hose and to a product container for delivery of a water/product mixture. The present invention is particularly useful as a multi-position sprayer assembly which allows for ergonomic operation with one hand for selective delivery of a water stream, a water/product stream or a water/product spray.
Every year thousands of gallons of chemicals such as fertilizers or pesticides are applied to crops, plants, lawns, flowers, vegetable gardens and other organic type vegetation. Sprayed chemicals are also used as cleaning agents for homes and automobiles. Such chemical products are sold to consumers in concentrated form and therefore may be hazardous to the consumer and environment in general. Accordingly, the containers for the chemicals typically have a spray assembly permanently attached thereto. The sprayer assembly allows for delivery of the chemicals in a diluted form, usually as a chemical product/water mixture.
To allow for mixing with water, a typical sprayer assembly has a structure in which a fluid communication path exists between the concentrated product container and the sprayer assembly. During operation, an inlet end of the assembly is attached to a water source (usually a garden hose), and water is forced through the assembly. As the water flows past the fluid communication path for the product, a Venturi effect is created in accordance with well-known scientific principles which draws product out of the container. The product mixes with the water to create a water/product mixture which is then sprayed out an outlet end of the assembly. These sprayers are known in the art as aspiration-type sprayers.
Current aspiration sprayer assemblies are relatively complex in design, require many molded parts and are difficult to assemble in an economic method. For example, U.S. Pat. No. 5,213,265, which issued to Englhard et al. for an invention entitled xe2x80x9cSingle Valve Aspiration Type Sprayerxe2x80x9d, discloses an aspiration type sprayer for dispensing small quantities of a liquid based chemical into a stream of carrier fluid. For the device as recited in Englhard, however, the sprayer valve is attached to the top of the assembly. Thus, two hands are required to operate the assembly, which obviates any convenience advantages of the device. Further, the device disclosed by Englhard has a relatively complex construction, including at least three O-rings, to allow for operation of the device without leakage. Finally, the sprayer valve (when open) directs a solid stream of carrier fluid (water) onto a deflector plate, where it mixes with the pesticide/fertilizer. The deflector plate delivers a fan spray, and only a fan spray, of water/pesticide mixture. Stated, differently, the device is not capable of selective delivery of a water only stream, a water/product mixture stream or a water/product mixture spray.
U.S. Pat. No. 5,954,272, which issued to Liao for an invention entitled xe2x80x9cDetergent/Water Mixing System For a Water Spray Gunxe2x80x9d, discloses a device including a gun body having a water inlet, a water outlet, a cylindrical transverse through-hole in communication with the water inlet and the water outlet, and a control valve mounted in the through-hole. Liao also discloses a detergent container which can be attached to the gun body to allow for delivery of a detergent/water mixture. There are critical differences in structure, however, between the device disclosed by Liao and the present invention which render the device of Liao inappropriate for aspiration applications.
The device of Liao has a valve body with a water chamber which is in fluid communication with the water inlet of the device and an ejector in fluid communication with the water chamber and with a detergent container. This structure causes water to be directed from the water ejector into the detergent container. The water agitates the detergent concentrate and the water flow is then directed back out of the detergent container via a guide hole which is in communication with a water outlet chamber in the valve body.
For the device disclosed by Liao, the detergent container is in fluid communication with the water inlet. Accordingly, the structure of the device disclosed by Liao causes water to be forced into the detergent container to further force an uncontrolled water/detergent mixture out of the container. There is no Venturi effect which draws water from the container, and, thus, no aspiration of detergent from the container. In fact, the sprayer assembly described by Liao is not appropriate for sensitive chemical applications. This is because the uncontrolled water flow into a chemical concentrate container yields an uncontrolled ratio of product/water mixture out of the sprayer assembly, which is an undesirable condition.
In light of the above, it is an object of the present invention to provide a sprayer assembly which has a very simple structure with an absolute minimum of parts, and yet delivers the product/water mixture without leakage. It is another object of the present invention to provide an aspiration type sprayer assembly which allows for selective delivery of a water stream, a water/product stream, or a water/product fan spray. It is another object of the present invention to provide a sprayer assembly which allows for ergonomic operation with one hand, in order to maintain more control over a container/sprayer assembly combination. Since the associated container is non-refillable, it is yet another object of the present invention to provide a sprayer assembly that has a sufficiently low manufacturing cost that the container/sprayer arrangement can be discarded when the container contents have been completely used.
A sprayer assembly in accordance with the present invention includes a housing having an elastomeric membrane that is integrally molded to the housing in a co-molding process known in the art. The membrane inner surface defines a transverse opening in the housing. An outlet aperture extends through the housing from the outer surface of the housing to the inner surface of the membrane. Similarly, a inlet orifice and an aspiration orifice exits through the housing from the housing outside surface to the inner surface of the membrane. A hollow handle and a hollow coupling are further attached to the housing. The handle defines a chamber which is in fluid communication the housing inlet orifice and the coupling allows for fluid communication with a product container.
The assembly of the present invention further includes a trigger body which is inserted in the transverse opening and rotatably mounted to the body. The trigger body is formed with an inlet port, an outlet port which is in fluid communication with the inlet port, and an aspiration port which is in communication with the outlet port.
The trigger body can be selectively rotated so that when the aspiration port is isolated from the aspiration orifice, the inlet port is in communication with the inlet orifice and the outlet port is in communication with the outlet aperture. Once the handle is connected to a water source, this alignment allows for a water only stream during operation of the present invention.
Alternatively, the valve body can be rotated so that the inlet port, outlet port and aspiration port of the body are all in fluid communication with the respective inlet orifice, outlet orifice and aspiration orifice of the housing.. This alignment creates a Venturi effect which draws product out of the container into the outlet port of the body. The concentrate product mixes with water in the outlet port, and the water/product mixture stream is directed out the outlet aperture of the housing.
Further rotation of the valve body maintains the above alignment but changes the flow path of the mixture. Specifically, the mixture stream is directed onto a deflector plate which is mounted to the outside surface of the housing. This yields a fan spray of the water/product mixture.